<?php

namespace GetId3\Module\Audio;

use GetId3\Handler\BaseHandler;
use GetId3\Lib\Helper;
use GetId3\GetId3Core;
use GetId3\Module\AudioVideo\Riff;

/////////////////////////////////////////////////////////////////
/// GetId3() by James Heinrich <info@getid3.org>               //
//  available at http://getid3.sourceforge.net                 //
//            or http://www.getid3.org                         //
/////////////////////////////////////////////////////////////////
// See readme.txt for more details                             //
/////////////////////////////////////////////////////////////////
//                                                             //
// module.audio.wavpack.php                                    //
// module for analyzing WavPack v4.0+ Audio files              //
// dependencies: NONE                                          //
//                                                            ///
/////////////////////////////////////////////////////////////////

/**
 * module for analyzing WavPack v4.0+ Audio files
 *
 * @author James Heinrich <info@getid3.org>
 *
 * @link http://getid3.sourceforge.net
 * @link http://www.getid3.org
 */
class Wavpack extends BaseHandler
{
    /**
     * @return bool
     */
    public function analyze()
    {
        $info = &$this->getid3->info;

        fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);

        while (true) {
            $wavpackheader = fread($this->getid3->fp, 32);

            if (ftell($this->getid3->fp) >= $info['avdataend']) {
                break;
            } elseif (feof($this->getid3->fp)) {
                break;
            } elseif (
                isset($info['wavpack']['blockheader']['total_samples']) &&
                isset($info['wavpack']['blockheader']['block_samples']) &&
                ($info['wavpack']['blockheader']['total_samples'] > 0) &&
                ($info['wavpack']['blockheader']['block_samples'] > 0) &&
                (!isset($info['wavpack']['riff_trailer_size']) || ($info['wavpack']['riff_trailer_size'] <= 0)) &&
                ((isset($info['wavpack']['config_flags']['md5_checksum']) && ($info['wavpack']['config_flags']['md5_checksum'] === false)) || !empty($info['md5_data_source']))) {
                break;
            }

            $blockheader_offset = ftell($this->getid3->fp) - 32;
            $blockheader_magic = substr($wavpackheader, 0, 4);
            $blockheader_size = Helper::LittleEndian2Int(substr($wavpackheader, 4, 4));

            $magic = 'wvpk';
            if ($blockheader_magic != $magic) {
                $info['error'][] = 'Expecting "'.Helper::PrintHexBytes($magic).'" at offset '.$blockheader_offset.', found "'.Helper::PrintHexBytes($blockheader_magic).'"';
                switch (isset($info['audio']['dataformat']) ? $info['audio']['dataformat'] : '') {
                    case 'wavpack':
                    case 'wvc':
                        break;
                    default:
                        unset($info['fileformat']);
                        unset($info['audio']);
                        unset($info['wavpack']);
                        break;
                }

                return false;
            }

            if (empty($info['wavpack']['blockheader']['block_samples']) ||
                empty($info['wavpack']['blockheader']['total_samples']) ||
                ($info['wavpack']['blockheader']['block_samples'] <= 0) ||
                ($info['wavpack']['blockheader']['total_samples'] <= 0)) {
                // Also, it is possible that the first block might not have
                // any samples (block_samples == 0) and in this case you should skip blocks
                // until you find one with samples because the other information (like
                // total_samples) are not guaranteed to be correct until (block_samples > 0)

                // Finally, I have defined a format for files in which the length is not known
                // (for example when raw files are created using pipes). In these cases
                // total_samples will be -1 and you must seek to the final block to determine
                // the total number of samples.

                $info['audio']['dataformat'] = 'wavpack';
                $info['fileformat'] = 'wavpack';
                $info['audio']['lossless'] = true;
                $info['audio']['bitrate_mode'] = 'vbr';

                $info['wavpack']['blockheader']['offset'] = $blockheader_offset;
                $info['wavpack']['blockheader']['magic'] = $blockheader_magic;
                $info['wavpack']['blockheader']['size'] = $blockheader_size;

                if ($info['wavpack']['blockheader']['size'] >= 0x100000) {
                    $info['error'][] = 'Expecting WavPack block size less than "0x100000", found "'.$info['wavpack']['blockheader']['size'].'" at offset '.$info['wavpack']['blockheader']['offset'];
                    switch (isset($info['audio']['dataformat']) ? $info['audio']['dataformat'] : '') {
                        case 'wavpack':
                        case 'wvc':
                            break;
                        default:
                            unset($info['fileformat']);
                            unset($info['audio']);
                            unset($info['wavpack']);
                            break;
                    }

                    return false;
                }

                $info['wavpack']['blockheader']['minor_version'] = ord($wavpackheader{8});
                $info['wavpack']['blockheader']['major_version'] = ord($wavpackheader{9});

                if (($info['wavpack']['blockheader']['major_version'] != 4) ||
                    (($info['wavpack']['blockheader']['minor_version'] < 4) &&
                    ($info['wavpack']['blockheader']['minor_version'] > 16))) {
                    $info['error'][] = 'Expecting WavPack version between "4.2" and "4.16", found version "'.$info['wavpack']['blockheader']['major_version'].'.'.$info['wavpack']['blockheader']['minor_version'].'" at offset '.$info['wavpack']['blockheader']['offset'];
                    switch (isset($info['audio']['dataformat']) ? $info['audio']['dataformat'] : '') {
                            case 'wavpack':
                            case 'wvc':
                                break;
                            default:
                                unset($info['fileformat']);
                                unset($info['audio']);
                                unset($info['wavpack']);
                                break;
                        }

                    return false;
                }

                $info['wavpack']['blockheader']['track_number'] = ord($wavpackheader{10}); // unused
                $info['wavpack']['blockheader']['index_number'] = ord($wavpackheader{11}); // unused
                $info['wavpack']['blockheader']['total_samples'] = Helper::LittleEndian2Int(substr($wavpackheader, 12, 4));
                $info['wavpack']['blockheader']['block_index'] = Helper::LittleEndian2Int(substr($wavpackheader, 16, 4));
                $info['wavpack']['blockheader']['block_samples'] = Helper::LittleEndian2Int(substr($wavpackheader, 20, 4));
                $info['wavpack']['blockheader']['flags_raw'] = Helper::LittleEndian2Int(substr($wavpackheader, 24, 4));
                $info['wavpack']['blockheader']['crc'] = Helper::LittleEndian2Int(substr($wavpackheader, 28, 4));

                $info['wavpack']['blockheader']['flags']['bytes_per_sample'] = 1 + ($info['wavpack']['blockheader']['flags_raw'] & 0x00000003);
                $info['wavpack']['blockheader']['flags']['mono'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000004);
                $info['wavpack']['blockheader']['flags']['hybrid'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000008);
                $info['wavpack']['blockheader']['flags']['joint_stereo'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000010);
                $info['wavpack']['blockheader']['flags']['cross_decorrelation'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000020);
                $info['wavpack']['blockheader']['flags']['hybrid_noiseshape'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000040);
                $info['wavpack']['blockheader']['flags']['ieee_32bit_float'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000080);
                $info['wavpack']['blockheader']['flags']['int_32bit'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000100);
                $info['wavpack']['blockheader']['flags']['hybrid_bitrate_noise'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000200);
                $info['wavpack']['blockheader']['flags']['hybrid_balance_noise'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000400);
                $info['wavpack']['blockheader']['flags']['multichannel_initial'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00000800);
                $info['wavpack']['blockheader']['flags']['multichannel_final'] = (bool) ($info['wavpack']['blockheader']['flags_raw'] & 0x00001000);

                $info['audio']['lossless'] = !$info['wavpack']['blockheader']['flags']['hybrid'];
            }

            while (!feof($this->getid3->fp) && (ftell($this->getid3->fp) < ($blockheader_offset + $blockheader_size + 8))) {
                $metablock = array('offset' => ftell($this->getid3->fp));
                $metablockheader = fread($this->getid3->fp, 2);
                if (feof($this->getid3->fp)) {
                    break;
                }
                $metablock['id'] = ord($metablockheader{0});
                $metablock['function_id'] = ($metablock['id'] & 0x3F);
                $metablock['function_name'] = $this->WavPackMetablockNameLookup($metablock['function_id']);

                // The 0x20 bit in the id of the meta subblocks (which is defined as
                // ID_OPTIONAL_DATA) is a permanent part of the id. The idea is that
                // if a decoder encounters an id that it does not know about, it uses
                // that "ID_OPTIONAL_DATA" flag to determine what to do. If it is set
                // then the decoder simply ignores the metadata, but if it is zero
                // then the decoder should quit because it means that an understanding
                // of the metadata is required to correctly decode the audio.
                $metablock['non_decoder'] = (bool) ($metablock['id'] & 0x20);

                $metablock['padded_data'] = (bool) ($metablock['id'] & 0x40);
                $metablock['large_block'] = (bool) ($metablock['id'] & 0x80);
                if ($metablock['large_block']) {
                    $metablockheader .= fread($this->getid3->fp, 2);
                }
                $metablock['size'] = Helper::LittleEndian2Int(substr($metablockheader, 1)) * 2; // size is stored in words
                $metablock['data'] = null;

                if ($metablock['size'] > 0) {
                    switch ($metablock['function_id']) {
                        case 0x21: // ID_RIFF_HEADER
                        case 0x22: // ID_RIFF_TRAILER
                        case 0x23: // ID_REPLAY_GAIN
                        case 0x24: // ID_CUESHEET
                        case 0x25: // ID_CONFIG_BLOCK
                        case 0x26: // ID_MD5_CHECKSUM
                            $metablock['data'] = fread($this->getid3->fp, $metablock['size']);

                            if ($metablock['padded_data']) {
                                // padded to the nearest even byte
                                --$metablock['size'];
                                $metablock['data'] = substr($metablock['data'], 0, -1);
                            }
                            break;

                        case 0x00: // ID_DUMMY
                        case 0x01: // ID_ENCODER_INFO
                        case 0x02: // ID_DECORR_TERMS
                        case 0x03: // ID_DECORR_WEIGHTS
                        case 0x04: // ID_DECORR_SAMPLES
                        case 0x05: // ID_ENTROPY_VARS
                        case 0x06: // ID_HYBRID_PROFILE
                        case 0x07: // ID_SHAPING_WEIGHTS
                        case 0x08: // ID_FLOAT_INFO
                        case 0x09: // ID_INT32_INFO
                        case 0x0A: // ID_WV_BITSTREAM
                        case 0x0B: // ID_WVC_BITSTREAM
                        case 0x0C: // ID_WVX_BITSTREAM
                        case 0x0D: // ID_CHANNEL_INFO
                            fseek($this->getid3->fp, $metablock['offset'] + ($metablock['large_block'] ? 4 : 2) + $metablock['size'], SEEK_SET);
                            break;

                        default:
                            $info['warning'][] = 'Unexpected metablock type "0x'.str_pad(dechex($metablock['function_id']), 2, '0', STR_PAD_LEFT).'" at offset '.$metablock['offset'];
                            fseek($this->getid3->fp, $metablock['offset'] + ($metablock['large_block'] ? 4 : 2) + $metablock['size'], SEEK_SET);
                            break;
                    }

                    switch ($metablock['function_id']) {
                        case 0x21: // ID_RIFF_HEADER
                            $original_wav_filesize = Helper::LittleEndian2Int(substr($metablock['data'], 4, 4));

                            $getid3_temp = new GetId3Core();
                            $getid3_temp->openfile($this->getid3->filename);
                            $getid3_riff = new Riff($getid3_temp);
                            $getid3_riff->ParseRIFFdata($metablock['data']);
                            $metablock['riff'] = $getid3_temp->info['riff'];
                            $info['audio']['sample_rate'] = $getid3_temp->info['riff']['raw']['fmt ']['nSamplesPerSec'];
                            unset($getid3_riff, $getid3_temp);

                            $metablock['riff']['original_filesize'] = $original_wav_filesize;
                            $info['wavpack']['riff_trailer_size'] = $original_wav_filesize - $metablock['riff']['WAVE']['data'][0]['size'] - $metablock['riff']['header_size'];
                            $info['playtime_seconds'] = $info['wavpack']['blockheader']['total_samples'] / $info['audio']['sample_rate'];

                            // Safe RIFF header in case there's a RIFF footer later
                            $metablockRIFFheader = $metablock['data'];
                            break;

                        case 0x22: // ID_RIFF_TRAILER
                            $metablockRIFFfooter = $metablockRIFFheader.$metablock['data'];

                            $startoffset = $metablock['offset'] + ($metablock['large_block'] ? 4 : 2);
                            $getid3_temp = new GetId3Core();
                            $getid3_temp->openfile($this->getid3->filename);
                            $getid3_temp->info['avdataend'] = $info['avdataend'];
                            $getid3_temp->info['fileformat'] = 'riff';
                            $getid3_riff = new Riff($getid3_temp);
                            $metablock['riff'] = $getid3_riff->ParseRIFF($startoffset, $startoffset + $metablock['size']);

                            if (!empty($metablock['riff']['INFO'])) {
                                $getid3_riff->RIFFcommentsParse($metablock['riff']['INFO'], $metablock['comments']);
                                $info['tags']['riff'] = $metablock['comments'];
                            }
                            unset($getid3_temp, $getid3_riff);
                            break;

                        case 0x23: // ID_REPLAY_GAIN
                            $info['warning'][] = 'WavPack "Replay Gain" contents not yet handled by GetId3Core() in metablock at offset '.$metablock['offset'];
                            break;

                        case 0x24: // ID_CUESHEET
                            $info['warning'][] = 'WavPack "Cuesheet" contents not yet handled by GetId3Core() in metablock at offset '.$metablock['offset'];
                            break;

                        case 0x25: // ID_CONFIG_BLOCK
                            $metablock['flags_raw'] = Helper::LittleEndian2Int(substr($metablock['data'], 0, 3));

                            $metablock['flags']['adobe_mode'] = (bool) ($metablock['flags_raw'] & 0x000001); // "adobe" mode for 32-bit floats
                            $metablock['flags']['fast_flag'] = (bool) ($metablock['flags_raw'] & 0x000002); // fast mode
                            $metablock['flags']['very_fast_flag'] = (bool) ($metablock['flags_raw'] & 0x000004); // double fast
                            $metablock['flags']['high_flag'] = (bool) ($metablock['flags_raw'] & 0x000008); // high quality mode
                            $metablock['flags']['very_high_flag'] = (bool) ($metablock['flags_raw'] & 0x000010); // double high (not used yet)
                            $metablock['flags']['bitrate_kbps'] = (bool) ($metablock['flags_raw'] & 0x000020); // bitrate is kbps, not bits / sample
                            $metablock['flags']['auto_shaping'] = (bool) ($metablock['flags_raw'] & 0x000040); // automatic noise shaping
                            $metablock['flags']['shape_override'] = (bool) ($metablock['flags_raw'] & 0x000080); // shaping mode specified
                            $metablock['flags']['joint_override'] = (bool) ($metablock['flags_raw'] & 0x000100); // joint-stereo mode specified
                            $metablock['flags']['copy_time'] = (bool) ($metablock['flags_raw'] & 0x000200); // copy file-time from source
                            $metablock['flags']['create_exe'] = (bool) ($metablock['flags_raw'] & 0x000400); // create executable
                            $metablock['flags']['create_wvc'] = (bool) ($metablock['flags_raw'] & 0x000800); // create correction file
                            $metablock['flags']['optimize_wvc'] = (bool) ($metablock['flags_raw'] & 0x001000); // maximize bybrid compression
                            $metablock['flags']['quality_mode'] = (bool) ($metablock['flags_raw'] & 0x002000); // psychoacoustic quality mode
                            $metablock['flags']['raw_flag'] = (bool) ($metablock['flags_raw'] & 0x004000); // raw mode (not implemented yet)
                            $metablock['flags']['calc_noise'] = (bool) ($metablock['flags_raw'] & 0x008000); // calc noise in hybrid mode
                            $metablock['flags']['lossy_mode'] = (bool) ($metablock['flags_raw'] & 0x010000); // obsolete (for information)
                            $metablock['flags']['extra_mode'] = (bool) ($metablock['flags_raw'] & 0x020000); // extra processing mode
                            $metablock['flags']['skip_wvx'] = (bool) ($metablock['flags_raw'] & 0x040000); // no wvx stream w/ floats & big ints
                            $metablock['flags']['md5_checksum'] = (bool) ($metablock['flags_raw'] & 0x080000); // compute & store MD5 signature
                            $metablock['flags']['quiet_mode'] = (bool) ($metablock['flags_raw'] & 0x100000); // don't report progress %

                            $info['wavpack']['config_flags'] = $metablock['flags'];

                            $info['audio']['encoder_options'] = '';
                            if ($info['wavpack']['blockheader']['flags']['hybrid']) {
                                $info['audio']['encoder_options'] .= ' -b???';
                            }
                            $info['audio']['encoder_options'] .= ($metablock['flags']['adobe_mode']     ? ' -a' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['optimize_wvc']   ? ' -cc' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['create_exe']     ? ' -e' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['fast_flag']      ? ' -f' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['joint_override'] ? ' -j?' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['high_flag']      ? ' -h' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['md5_checksum']   ? ' -m' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['calc_noise']     ? ' -n' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['shape_override'] ? ' -s?' : '');
                            $info['audio']['encoder_options'] .= ($metablock['flags']['extra_mode']     ? ' -x?' : '');
                            if (!empty($info['audio']['encoder_options'])) {
                                $info['audio']['encoder_options'] = trim($info['audio']['encoder_options']);
                            } elseif (isset($info['audio']['encoder_options'])) {
                                unset($info['audio']['encoder_options']);
                            }
                            break;

                        case 0x26: // ID_MD5_CHECKSUM
                            if (strlen($metablock['data']) == 16) {
                                $info['md5_data_source'] = strtolower(Helper::PrintHexBytes($metablock['data'], true, false, false));
                            } else {
                                $info['warning'][] = 'Expecting 16 bytes of WavPack "MD5 Checksum" in metablock at offset '.$metablock['offset'].', but found '.strlen($metablock['data']).' bytes';
                            }
                            break;

                        case 0x00: // ID_DUMMY
                        case 0x01: // ID_ENCODER_INFO
                        case 0x02: // ID_DECORR_TERMS
                        case 0x03: // ID_DECORR_WEIGHTS
                        case 0x04: // ID_DECORR_SAMPLES
                        case 0x05: // ID_ENTROPY_VARS
                        case 0x06: // ID_HYBRID_PROFILE
                        case 0x07: // ID_SHAPING_WEIGHTS
                        case 0x08: // ID_FLOAT_INFO
                        case 0x09: // ID_INT32_INFO
                        case 0x0A: // ID_WV_BITSTREAM
                        case 0x0B: // ID_WVC_BITSTREAM
                        case 0x0C: // ID_WVX_BITSTREAM
                        case 0x0D: // ID_CHANNEL_INFO
                            unset($metablock);
                            break;
                    }
                }
                if (!empty($metablock)) {
                    $info['wavpack']['metablocks'][] = $metablock;
                }
            }
        }

        $info['audio']['encoder'] = 'WavPack v'.$info['wavpack']['blockheader']['major_version'].'.'.str_pad($info['wavpack']['blockheader']['minor_version'], 2, '0', STR_PAD_LEFT);
        $info['audio']['bits_per_sample'] = $info['wavpack']['blockheader']['flags']['bytes_per_sample'] * 8;
        $info['audio']['channels'] = ($info['wavpack']['blockheader']['flags']['mono'] ? 1 : 2);

        if (!empty($info['playtime_seconds'])) {
            $info['audio']['bitrate'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds'];
        } else {
            $info['audio']['dataformat'] = 'wvc';
        }

        return true;
    }

    /**
     * @staticvar array $WavPackMetablockNameLookup
     *
     * @param  type $id
     *
     * @return type
     */
    public function WavPackMetablockNameLookup(&$id)
    {
        static $WavPackMetablockNameLookup = array(
            0x00 => 'Dummy',
            0x01 => 'Encoder Info',
            0x02 => 'Decorrelation Terms',
            0x03 => 'Decorrelation Weights',
            0x04 => 'Decorrelation Samples',
            0x05 => 'Entropy Variables',
            0x06 => 'Hybrid Profile',
            0x07 => 'Shaping Weights',
            0x08 => 'Float Info',
            0x09 => 'Int32 Info',
            0x0A => 'WV Bitstream',
            0x0B => 'WVC Bitstream',
            0x0C => 'WVX Bitstream',
            0x0D => 'Channel Info',
            0x21 => 'RIFF header',
            0x22 => 'RIFF trailer',
            0x23 => 'Replay Gain',
            0x24 => 'Cuesheet',
            0x25 => 'Config Block',
            0x26 => 'MD5 Checksum',
        );

        return (isset($WavPackMetablockNameLookup[$id]) ? $WavPackMetablockNameLookup[$id] : '');
    }
}
